Permitting a user to interact with a device or an application running on a device is useful in many different settings. For example, keyboards, mice, and joysticks are often included with electronic systems to enable a user to input data, manipulate data, and cause a processor of the system to cause a variety of other actions. Increasingly, however, touch-based input devices, such as keyboards, mice, and joysticks, are being replaced by, or supplemented with, devices that permit touch-free user interaction. For example, a system may include an image sensor to capture images of a user, including, for example, a user's hands and/or fingers. A processor may be configured to receive such images and cause actions to occur based on touch-free gestures performed by the user.
It may be desirable to permit a user to make a number of different touch-free gestures that can be recognized by a system. However, the number of different types of touch-free gestures that can be detected and acted upon by a system is often limited. Improvements in techniques for detecting and acting upon touch-free gestures are desirable.